The invention relates to magnetic disks and more particularly to accessing mechanism for the disks whereby an access arm and a magnetic head carried thereby may be moved between a selected pair of disks in a vertical stack.
It has previously been common practice to utilize separate prime movers for positioning an access arm and a magnetic head with respect to a vertical stack of magnetic disks for the vertical and horizontal movements necessary for the access arm and head. The vertical movement is necessary for access to a specific disk in the stack, and the horizontal movement is necessary to access the track area of that disk for reading and writing information. Such separate prime movers may include separate electric motors of the stepping type and lead screw mechanism attached to each of the motors.